Application of rubber or like coverings to large rolls



Sept. 5, 1939. F. s. BOWKER 2,172,005

APPLICATION OF RUBBER 0R LIKE COVERINGS TO LARGE ROLDS Filed June 14, 1937 3 Sheets-Sheet 1 Sept. 5, 1939. Ffs. BOWKER APPLICATION OF-RUBBER OR LIKE COYERINGS T0 LARGE ROLLS Filed June 14, 1957 3 Sheqts-Sheet 2 m w W N W m MM 7 mm, m f W fi M Q 8 L) N w/ 7 M w n J 0 F rag: m m 25%.; Hun 1 x v Q f O m Q w a. Q 1 kw m r 3 w w\ w. N W W N n N .MNJ, Nm 9 1 w ill fl H HO... a ul h m m l nvmmmmfl w 7 mm Vi 5-H, h N a; w v M my .MHM =5 5 .H mm mm 0 Mm v wn w O R R, mm MM //wn Sept. 5, 1939. F. s BQWKER 2,172,005

APPLICATION OF RUBBER OR LIKE COVERINGS T0 LARGE ROLLS Filed June 14, 1937 3 Sheets-Sheet 3 HIIIIIIIIP Patented Sept. 5, 1939 APPLICATION OF RUBBER OR LIKE COVERINGS T0 LARGE ROLLS Frank S. Bowker, Woonsocket, R. I.

Application June 14, 1937. Serial No. 148,143

12 Claims.

The present invention relates to an improved method of and apparatus for applying coverings of rubber or like plastic materials to the cylindrical surfaces of relatively large rolls, such as are used, for example, in paper-making machinery.

The application of rubber or like coverings to relatively small rolls can be readily effected by the use of molds or like devices, arranged around the roll, in spaced relation to its surface and adapted to be removed after the molten covering material has become hardened and set. But it is altogether impractical to adapt such molding practices to the rubber-covering of variegated sizes of large rolls, running sometimes two or three feet in diameter and upwards of twenty feet long. As a consequence, the practice heretofore with such large rolls of various sizes has been to provide the covering material in the form of semi-plastic sheets, these being wrapped or drawn onto the roll so as to cover more or less loosely the latters roughened or grooved circumferential surface; then, several workmen, equipped with hand tools in the form usually of small rollers, are assigned to the task of pressing and working such covering wraps of the material into intimate engagement with the roughened and grooved roll surface, as well as the task of rolling out the semi-plastic material of the several wraps into a homogeneous layer of uniform thickness; thereafter, the covering is vulcanized and finally finished by grinding.

The application of rubber coverings to large rolls by the above-described procedure is an eX- ceedingly slow and costly process requiring, because of the large area that has to be rolled and tooled manually, the prolonged efforts and 'attention of many workmen. I Moreover, even with such expenditures for labor and with the exercise of the greatest care and skill in this hand rolling of the covering material, the results are far from satisfactory; for example, the covering in some places may be of considerably greater density than in other places, on account of one workman having rolled with greater pressure than another workman, or the covering may vary in thickness for a similar reason, or the bond of the covering with the surface of the roll may be strong in some places and weak in others. All such and similar inequalities, resulting primarily from the need for so many operators in the covering process, detract materially from the serviceability of the covered roll, and from its useful life.

The object of the present invention is to overcome and eliminate, in the covering process; allof the above-mentioned difliculties,thereby to produce better rubber-covered rolls than have heretofore been produced, and at the same time to reduce materially the cost of the covering process. According to my invention, as hereinafter described in detail, the covering material is subjected over its entire area to mechanical rolling-out and pressing-on operations that do away entirely with the uncertainties of the hand rolling heretofore in use,-my invention including among other things a special organization of apparatus for this purpose. Other and further objects and advantages of the invention will be made apparent from the following detailed description thereof, reference being had in this connection to the accompanying drawings, wherein Fig. 1 is a view in side elevation, partly in section, of one form of apparatus suitable for carrying out my invention.

Figs. 2 and 3 are cross sectional views, the sections being taken respectively on the lines 2-2 and 3 3 of Fig. 1.

Fig. 4 is a view similar to Fig. 2, showing a modification.

Fig. 5 is a section on the line 5-5 of Fig. 1.

Fig. 6 is a wiring diagram.

Fig. '7 is a fragmentary view, similar to Fig. 2, showing a subsequent step in the covering process.

Fig. 8 is a fragmentary sectional view on the line 8-8 of Fig. 2.

Like reference characters refer to like parts in the differentv figures.

My invention provides for the subjection of the work (the large roll carrying wraps of sheet rubber), to periodic step-by-step angular displacements about its axis, these angular movements alternating with periods of dwell in which the roll is held stationary, for the passage from end to end thereof of suitable means for pressing and rolling-out therubber; following each such traverse of the pressing and rolling-out device or devices, the roll turns on its axis through an appro-v priate predetermined angle to present the nextadjacent section of its surface to the action of the pressing and rolling-out means, on the latters next-ensuing lengthwise traverse, until finally the whole circumferential surface of the roll has been uniformly and completely traversed by said pressing and rolling-out means.

An apparatus to obtain these actions may consist, as shown, of a base or bed provided by two spaced-apart parallel members I, l whose upper edges have longitudinal guides or ways 2, 2 for the back and forth reciprocatory movements of a carriage 3 that supports the pressing and rolling-out instrumentalities, as hereinafter de' scribed. Between said ways 2, 2 the bed members at one end are connected by a bridge 4, on which is supported a headstock 5, the latter, as hereinafter described, having associated therewith the actuating devices that impart the aforesaid step-by-step rotative movements to the large rubber-covered roll A. At the other end, the bed. members I, l are spanned by a bridge 6, having suitable ways or guides 7, l thereon for the in and out movements of a slide 8 carrying a tailstock 9, the latter providing a suitable dead center is in alinement with a live center ll of headstock 5. These two centers Hi and H, the former being adjustable in or out to accommodate rolls of different lengths, provide the means by which the roll-A is supported for the aforesaid step-by-step angular movements about its axis, said centers preferably engaging, as shown, the end trunnions I2, E2 of the roll A, the latter being suitably supplied, from end to end of its grooved circumferential surface, with the usual encircling wraps a, a of soft rubber, which may be progressively drawn onto the roll by the latters angular movements, each followed by a pressing and rolling out of the strips of rubber so drawn on.

'Any suitable means may be employed for obtaining back and forth movements of the carriage 3 that occur in the periods of dwell between the regular step-by-step angular movements imparted to the roll A. As herein shown by way of example, a pressure fluid reciprocating mechanism for the carriage 3 may be employed; to this end, a bracket l3 projecting from the carriage is secured at its free end to the rod I l of a piston l5, the latter being movable within a suitably-supported cylinder it; which is somewhat longer than the longest roll that the machine is designed to handle. The interior of cylinder I6, by pipes I! and I8 communicating with the opposite ends thereof, is connected to the interior of a valve casing E9, the latter containing a reversing valve 261 for controlling the flow of fluid under pressure to and from the cylinder 16; said valve 20 provides two passages or ports 2| and 22, and in the position shown by Fig. l, the valve passage 2i connects the pipe l8 with a fluid pressure supply pipe 23 that leads from the outlet of a pump 2d drawing the fluid from a supply tank 25, thereby forcing the fluid into the left hand end of cylinder is to drive the piston l5 and carriage 3 to the right. In this illustrated position of the valve 23, its other passage 22 connects the pipe 51 to an exhaust or return pipe 26 leading back to the tank 25. In the other position into which the valve 29 is rocked, as hereinafter described, by the completion of the right hand movement of carriage 3, the passage 2| connects the pipe I? to the supply pipe 23, while the valve passage 22 connects the pipe E3 to the return pipe 23, thereby forcing fluid under pressure into the right hand end of the cylinder is to cause a left hand movement of piston l5 and carriage 3.

Projecting upwardly from the stem of valve 23 is an arm 2?, having a connection at 28 with a pivotally mounted reversing lever 29, the lat ter standing in the path of a pair of spaced oppositely acting dogs 33 and 31 carried by the table 3 and adapted alternately to strike and rock the lever 29 so as to throw the reversing valve 29 from one operative position to the other operative position and vice versa. The dogs 30 and SI are spaced apart on the carriage a dis tance somewhat in excess of the length of the roll A being operated upon; each dog is adjustably clamped to the carriage so that it can be set at different distances apart from the other dog, to correspond to variations in length of different rolls, thus to make the length of travel of carriage 3 appropriate to and always somewhat greater than the length of the roll A being operated upon.

The carriage 3 provides a transverse guide 32 for the support and guidance of a slide 33, the latter having an integrally extending portion 34 which terminates in a bearing or head 35, substantially in the horizontal plane of the centers I0 and l l on which the roll A is mounted. Said head 35 provides a suitable socket or bore 36 in substantially radial relation to the axis of the roll A for the reception of a bar 31, the latter having a snug sliding fit in said bearing, but being prevented from turning therein either by means of a key 38 and slot 39 as shown, or by making said bar of square cross section, to fit a correspondingly shaped bore or socket 36. The inner end of bar 31, beyond a shoulder 40 thereon, has detachably secured thereto a yoke 4|, the latter, when mounted on the bar, providing upper and lower bearings for a vertically disposed roller 42 whose surface, as shown, is concave from end to end, on a curvature substantially corresponding to the curvature of the particular roll A which is being operated upon. That is to say, there Will be provided in practice a plurality of these detachable pressure rollers 42 of varying degrees of concavity, to adapt them to the different curvatures, ofthe rolls that are operated upon in the machine! a large diameter roll requiring the use of a pressure roller of less concavity than would a roll of smaller diameter. A spring 43, surrounding the bar 31 and confined between the latters shoulder 40 and the head 35, is effective to thrust the pressure roller 42 yieldingly against the rubber which by the previously-occurring angular movement of roll A has been drawn onto the latters' surface in the zone of movement of roller 42, Said roller 42, by travel of the carriage 3, is moved along from one end to the other of roll A, pressing and rolling out the rubber, and effecting its intimate union with the grooved or roughened surface of roll A,the degree of pressure exerted being dependent upon the position of the slide 33.

According to my invention, the transverse guide 32 may provide a single roller-equipped slide 33, in which case the roller 42 would be used for the entire 360 of the circumference of roll A,--or, if desired, as shown in Fig. 2, a pair of roller-equipped slides 33 may be employed, with their rollers 42 in diametrically opposed relation on opposite sides of the roll A, in which case each roller 42 needs to work over only of the circumference of roll A. With this last-named arrangement, it is preferable to adjust the two,

Fig. 4 shows a somewhat modified construc- Z5,

tion in which the roller or rollers 42 are mounted in yokes 4i that are independently adjustable in and out with relation to the work roll A,-- each yoke for this purpose being connected to a screw 44' that works in a standard 33' rising directly from the carriage 3. To prevent a yoke from turning with its screw, an extension 35 on each yoke is slidably received in a suitable hole of the associated standard, the extension carrying, as shown, the compression spring 43 which is operative to urge the roller 42 yieldingly toward the work roll A.

In either case, the arrangement permits not only the substitution of rollers 42 of varying degrees of concavity to conform to different sizes of rubber-covered rolls A, but also the replacement of the vertically disposed concave roller or rollers 42 with a horizontally disposed cylindrical roller Bl (Fig. 7) this roller is used, as hereinafter described, to obtain, after the end-to-end rolling by the roller or rollers 42 has been completed, a circumferential rolling of the rubbercovered roll A, the latter, for the purpose of this circumferential rolling being continuously rotated by any suitable means. The pressure for this circumferential rolling by roller 61 can be adjusted in the same manner as for the end-toend rolling.

It has heretofore been mentioned that the throw or travel of the carriage 3, by which to move the roller or rollers 42 from end to end of the work roll A, is somewhat in excess of the length of said work roll; in other words, that the dogs 30 and 3| are so adjusted and spaced apart as to give the pressure roller or rollers 42 an appreciable over-run at each end of roll A. The reason for this is two-fold, viz., first, to offset the pressure applying devices from the surface of the roll A at such times as the latter is being rotated or indexed about its axis,-thusto relieve the rubber surface from any danger of being scraped or dug into by the pressure devices, and second, to give time for the rotary indexing motion to occur, before the pressure device or devices, after reversal of the carriage, resume travel along the work roll surface. This over-run of the pressure rollers at each end of the work roll is obtained by appropriate adjustment and spacing of the reversing dogs 35 and 3 I, being in each case of sufficient magnitude to give ample time for the indexing or work-rotating mechanism of the headstock 5 to function and to come to rest, before the pressure devices, on their reverse travel, move back onto the end of the work roll A.

In these zones of over-run of the roller or rollers 42 beyond both ends of the work roll A, means are provided to receive the pressure of said roller or rollers, since otherwise they might be forced by the springs 43 so far toward the axis of work roll A that on their ensuing reverse travel, they would not be able to climb back onto the cylindrical surface of said work roll. Accordingly, both the headstock 5 and the tailstock 8 are provided with slotted laterally extending brackets 46, 46; to these brackets are adjustably secured plates 41, 4'! arranged in the path of roller 42 on the front of the machine, and, if the machine uses also a pressure roller 42 at the rear, the similar adjustable plates 48, 48 to take the thrust of the rear roller in the zones of its over-run beyond the ends of the work roll A. The adjustment permits the plates 4? and 48-to be positioned as endwise extensions of the work roll surface, in the paths of movement of the pressing rollers,-and it will be understood that the strikingdogs 30 and 3| are so adjusted and spaced apart along the length of carriage 3 as to obtain the reversals of said carriages movement when the pressure rollers, at opposite ends of their travel, have over-run the work roll and are riding on the plates 41 and 48.

During each period of pressure roller contact with a plate 41 or 48 and while the work roll A is thus freed from the pressure of said rollers, said work roll is given, in any desired manner, the predetermined angular or indexing movement that moves into the path of the pressure roller or rollers 42 the rubber covered section or zone that immediately adjoins the just-rolled section of roll As surface. This indexing movement may be made to occur automatically, in response to the movement of the pressure roll 42 along either of the plates 47, 4'l,an illustrative arrangement of apparatus to secure this automatic indexing being shown diagrammatically in Fig. 6 and operating as follows:

Each plate 4'! carries, in the path of roller 42, an insulated resilient contact finger 49 that is struck and depressed by the roller 42 in its back and forth travel on the plate 4?; in the outward roller movement, the end of contact finger 49 is pressed momentarily into engagement with an insulated contact 55 supported by said plate. The finger 49 and contact 55 are arranged in a normally open electrical circuit which includes a solenoid 5|; said solenoid is energized whenever the roller 42, moving outwardly on either plate 41, depresses the associated finger 49 against the contact 50,--the two sets of contact devices being connected in parallel, as shown in Fig. 6, for this purpose. There is no energization of the solenoid 5i on the depressions of either finger 49 by the roller 42 on the latters inward movements (after reversal of carriage 3), the finger yielding in this case in a direction away from the associated contact 50, and then springing back to normal position after the roller has passed over.

The core or movable member 52 of solenoid 5! is connected to a s'lidable pin or plunger 53, the latter working in a suitable bearing 54 of headstock 5 and being pressed yieldingly by a spring 55 toward the periphery of a drum 5% provided at equal angular intervals with holes 5'5, 57 adapted to receive said pin, in order to lock said drum against rotation. The drum is mounted on a shaft or spindle 55 journalled in the headstock 5 and providing the live center it for the work roll A; the face of the drum provides a suitable driving dog 55 for cooperation with a projection Ell secured to the work roll, whereby the latter is made to partake of any rotative movement imported to said drum. It is to be understood however that in the major part of each traverse of the carriage 3 while the roller 42 is pressing on the surface of the work roll, the latter is held static-nary by the pin or plunger 53 seating in a hole 5? of the drum; only when the roller 42 has oven-run the work roll and moved onto a plate 41 can the work roll be rotated, this rotation being secured, for example, in the following manner:

At each energization of solenoid 54 (by the depression of finger 49 against contact 58), the core 52, overcoming spring 55, first draws the plunger or pin 53 out of the hole that it occupies (thus freeing the drum 55 for rotation), and immediately thereafter carries an insulated contact 6| on said core into engagement with an insulated stationary contact 62; the contacts El and 52 are arranged in a circuit that includes a variable-speed motor 63, whose shaft 6% has a worm and worm wheel connection 65 with the shaft 58 of drum 55, thus to impart by the operation of said motor a rotation very much reduced in speed to said drum and work roll A. This rotation, initiated by the withdrawal of pin 53 from hole 5'1, gets under way before the outwardly moving roller 22 clears the finger 49, allowing the latter to spring up, to open the circuit of the solenoid; hence the breaking of such circuit is without eifect, because the pin 53, when thus released by the solenoid and restored to the influence of spring 55, will nevertheless be prevented from breaking the motor circuit, by the contact of its end with the periphery of the rotating drum, this maintaining the motor circuit. When the next hole 51 arrives opposite the pin, the latter drops in under the influence of spring 55, this immediately breaking the motor circuit, whereby the indexing operation for the work roll is completed, the same occurring while the pressure roller 52 is still on the plate 41. After reversal of the carriage, to give the pressure rollers an inward movement toward the work roll, for operation on the newly-presented section of the latters surface, the front pressure roller again engages with the finger 49, but this is without effect on the circuit of the solenoid; thus the work roll remains locked by the pin in a stationary position to receive the ensuing pressing and rolling-out operation. Thereupon, the roller 42 on arrival against the plate fiat the other end of the work roll, again operatively engages a finger 49 to first energize the solenoid for the withdrawal of the pin, and then while the pin is withdrawn, to set the motor in operation for another indexing movement of the drum and work roll.

In the operation of the machine, the abovedescribed traverses of the pressure device or devices 42 are continued in alternating relation to the step-by-step angular indexing displacements of work roll A until the entire rubber-covered surface has been subjected uniformly to the pressing and rolling-out action. Thus the entire operation of pressing and rolling-out the covering that has heretofore required the services of numerous workmen is, by my invention, performed entirely by mechanical means,the machine after being set up and started requiring no attention other than that of a single workman or supervisor, whose principal duty is to prick any air bubbles formed from time to time in the semi-plastic covering. This attendant can make any necessary adjustment in the speed of the carriage 3 (by operation of a throttle valve 66 in pipe 23), and can from time to time make such adjustments of the slides 33 as will keep the rollers 42 operating at a substantially uniform pressure. At the conclusion of the end-to-end rolling, after the roller or rollers 32 have traversed the entire surface of work roll A and effected a uniform bond of union of the rubber with the grooved surface of said roll, the operator stops the machine. If desired, before the work roll is removed, for vulcanizing and the usual subsequent grinding of its surface, a circumferential rolling operation may be performed. To this end, the roller or rollers 32 are removed from their carrying slides and one of these slides is equipped with a cylindrical roller 61 (Fig. '7), having its axis parallel to that of the work roll A; for the operation of this horizontal roller 6'5, reversing dogs 30 and 3| are adjusted to give the carriage 3 a back and forth movement of a length substantially corresponding to the length of the work roll, and the latter is rotated continuously, at a somewhat higher speed than the indexing speed, as by holding the pin 53 retracted from drum 56 (thereby to keep the contacts BI and 52 in engagement) and by manipulating the controller 63 of the motor to obtain the desired increase in speed.

I claim:

In the application of rubber or like coverings to a large roll, the improvement which consists in arranging sheet rubber in covering relation to the cylindrical surface, of the roll producing longitudinal traverses of a pressure roller in a predetermined path on the rubbercovered surface, in alternating relation to stepby-step angular displacements of said surface until the whole rubber-covered surface has been acted upon by said pressure roller, and then subjecting said so-applied covering to circumferential rolling.

2. In the application of rubber or like coverings to large rolls, the improvement which consists in arranging sheet rubber in condition to be drawn onto a roll surface by the latters rotation, producing longitudinal traverses of a pressure roller in a predetermined path on the rubber-covered surface, in alternating relation to step-by-step angular displacements of said surface until the whole rubber-covered surface has been acted upon by said pressure roller, and then subjecting said so-applied covering to circumferential rolling by a roller having its axis substantially parallel to that of the rubber-covered large roll.

3. In apparatus for uniting a sheet rubber covering to the surface of a roll, means for imparting periodic angular movements to said roll and covering in unison, pressing means for operation on said rubber covering, to effect its union with the surface of said roll, and means alternating in operation with said first-mentioned means for producing end-to-end traverses of said roll by said pressing means and the latters rotation by its contact with said rubber.

4. In apparatus for uniting a sheet rubber covering to the surface of a roll, means for imparting periodic angular movements to said roll and covering in unison, means for holding said roll stationary between such angular movements, pressing means operable on the rubber covering to effect its union with the surface of said roll, and means operable during each stationary period of said roll for effecting the end-to-end traverse of same by said pressing means.

5. In apparatus for uniting a sheet rubber covering to the surface of a roll, means for imparting periodic angular movements, with intervening periods of dwell, to a said roll and covering in unison, a pressure roller for operation on said rubber covering, to eifect its union with the surface of said roll, and means for procuring endwise traverses of said roll by said pressure roller during said periods of dwell.

6. In apparatus for uniting a sheet rubber covering to the surface of a roll, means for imparting periodic angular movements, with intervening periods of dwell, to said roll and covering in unison, a pressure roller with its axis substantially at right angles to the axis of said roll and arranged for operation on said rubber coveing, to eifect its union with the surface of said roll, and means for procuring endwise traverses of said roll by said pressure roller during said periods of dwell.

'7. In apparatus for uniting a sheet rubber covering to the surface of a roll, the combination with pressing means adapted to reciprocate longitudinally of said roll and in contact with said covering, means for reversing the movements of said pressure means in zones beyond the ends of said roll, and devices arranged in said zones to receive the pressure of said pressing means.

8. In apparatus for uniting a sheet rubber covering to the surface of a roll, the combination with a pressure means adapted to reciprocate longitudinally of said roll and in contact with said covering, of means for reversing the movements of said pressure means in zones beyond the ends of said roll, and means operable while said pressure means are in said zones of reversal for imparting a predetermined angular movementto said roll.

9. In apparatus for uniting a sheet rubber covering to the surface of a roll, the combination with pressure means adapted to reciprocate longitudinally of said roll and in contact with said covering, of means for reversing the movements of said pressure means in zones beyond the ends of said roll, and means responsive to the arrival of said pressure means in a zone of reversal for shifting said roll angularly; to expose another section of its rubber -covered surface of the ensuing travel of said pressing means.

10. In apparatus for uniting a sheet rubber covering to the surface of a roll, the combination with pressure means adapted to reciprocate longitudinally of said roll and in contact with said covering, of means for reversing the movements of said pressure means in zones beyond the ends of said roll, and means operable during such reversals for producing an indexing movement of said roll on its axis of rotation before said pressure means moves from its reversing zone onto said rubber-covered surface.

11. In apparatus for uniting a sheet rubber covering to the surface of a roll, the combination with pressure means adapted to reciprocate longitudinally of said roll and in contact with said covering, of means for relieving said rubber covering from the pressure of said pressure means in the latters zones of reversal, and means operative in the periods of relief of such pressure for imparting angular indexing movements to said roll.

12. In apparatus for uniting a sheet rubber covering to the surface of a roll, the combination with pressure means adapted to reciprocate longitudinally of said roll and in contact with said covering, means for reversing the movements of said pressure means in zones beyond the ends of said roll, means in said zones, substantially flush with the rolls rubber-covered surface to receive the pressure of said pressure means during reversal thereof, and means operable during such reversals for producing an indexing movement of said roll before said pressure means again contacts the rubber covering of said roll.

' FRANK S. BOWKER. 

